1. Field of the Invention
The present invention is directed to finishing chrome plated materials, and in particular, to methods and apparatus for improving the corrosion resistance of chrome plated materials.
2. The Prior Art
Materials are chrome plated to reduce surface corrosion of the materials. Nevertheless, despite the chrome plating, surface corrosion still occurs and presents problems. This is particularly true in applications where there is intimate contact between the surface of the chrome plated materials and another material. Thus, for example, chrome plated rods used in hydraulic applications come into contact with seals made of rubber and similar materials. Surface corrosion of such rods has the additional disadvantage of causing accelerated wear of the seals. In use, such rods are subjected to high temperatures during operation of the equipment in which they are used, which increases the occurrence of corrosion.
In order to improve the corrosion resistance of chrome plated rods and the like, they are subjected in the prior art to a polishing process. A chrome plated rod is advanced along a line from an entrance end upon a series of pairs of offset rollers that both rotate and advance the rod from the entrance end to the exit end of the line Generally, after the rod is placed on the offset conveying rollers, the periphery of the chrome plated rod is initially subjected to wet abrasive polishing at one or more polishing stations. After such wet abrasive polishing, a buffing compound, of any of a selected one of a number of commercially available mixtures, is applied to the rotating chrome plated rod. Usually such buffing compounds are applied in a multi-phase mixture by spraying them onto the rotating and advancing rod.
The prior art process then subjects the rod, with the buffing compound applied, to a series of buffing steps at a number of buffing stations. Generally, three buffing stations are used in the prior art to provide the required amount of polishing or buffing to sufficiently drive the buffing compound into the micro cracks in the chrome plated surface. Thus, open micro cracks in the chrome plated surface are sealed against corrosion by the impregnated buffing compound.
In such prior art processes, as the compound treated chrome plated surface is subjected to more polishing or buffing, it results in a higher surface finish. Thus, in the prior art process of improving the corrosion resistance of chrome plated materials, there is a corollary between the degree of surface finish and the expected resultant corrosion resistance. However, particularly in hydraulic applications, there is a disadvantage to having too high of a surface finish as it impedes the effectiveness of the cooperating seals. Nevertheless, if the corrosion resistance of the chrome plated rods is not significantly improved by an application of a buffing compound, there will be a resulting increase in downtime of production of the hydraulic equipment while the corroded rods and/or the ruined seals need to be replaced.
Accordingly, it would be desirable to provide a method and apparatus for improving the corrosion resistance of chrome plated materials, in order to increase the life of such materials and to decrease the downtime of machines in which they are used.
These and other desirable characteristics of the present invention will become apparent in light of the present specification, including claims, and drawings.
The present invention is directed, in part, to an apparatus for improving the corrosion resistance of chrome plated materials. The apparatus comprises a line for receiving and processing chrome plated materials. The line has an entrance at one, entrance end, and an exit at another, exit end, opposed to the one entrance end. The apparatus further comprises a mechanism for moving the received chrome plated materials along the line from the one entrance end to the other exit end during processing, an applicator intermediate the one entrance end and the other exit end for applying a buffing compound, a heater for heating both the chrome plated materials and the buffing compounds, and at least one buffer for buffing the heated chrome plated materials and the buffing compound.
The heater may be positioned after the applicator and before the at least one buffer as the chrome plated materials move from the one entrance end to the other exit end.
The buffing compound has a melting point and the heater heats the chrome plated materials to a temperature above the melting point of the buffing compound. The heater heats the chrome plated material to approximately 160xc2x0 F. In the preferred embodiment, the heater is an induction coil, though other forms of heat source are contemplated, such as conduction or convection heaters.
The apparatus further comprises a rotating buffer, though there may be a plurality of rotating buffers.
The applicator is a sprayer and the buffing compound is applied by spraying it onto the chrome plated materials.
The heater may be computer controlled in response to input of a size factor of the chrome plated materials.
The present invention is also directed, at least in part, to a method for improving the corrosion resistance of chrome plated materials comprising the steps of:
applying a buffing compound to the chrome plated materials;
heating the chrome plated materials;
buffing the heated chrome plated materials after the buffing compound has been applied.
In the method of the present invention, the step of applying the buffing compound may be accomplished by spraying it onto the chrome plated materials. Moreover, the step of heating chrome plated materials may be done after the step of applying the buffing compound.
In the method of the present invention, the buffing compound has a melting point and the chrome plated materials and the buffing compound are heating above the melting point of the buffing compound. Thus, the chrome plated materials may be heated to approximately 160xc2x0 F. In such case, the buffing occurs before the chrome plated materials cool down below approximately 140xc2x0 F.
For that embodiment in which the heating step is effected by an induction coil, controlling the heating of the chrome plated material may be accomplished by a computer responsive to input of one or more factors, such as speed of movement, size and composition of the chrome plated material.
The buffing step in the present invention may be accomplished by at least one rotating buffing wheel, or by a plurality of buffing wheels.
The method of the present invention may also comprise the step of advancing the chrome plated materials along a line from one entrance end to an opposed exit end, with the steps of applying the buffing compound, heating the chrome plated materials and buffing the heated chrome plated material with the buffing compound applied being accomplished at discrete intervals along the line from the one entrance end to the other exit end.